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        <h2>Table of Contents</h2>
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<li><a href="#tty_tty">TTY</a><ul>
<li><a href="#tty_class_readstream">Class: ReadStream</a><ul>
<li><a href="#tty_rs_israw">rs.isRaw</a></li>
<li><a href="#tty_rs_setrawmode_mode">rs.setRawMode(mode)</a></li>
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<li><a href="#tty_class_writestream">Class: WriteStream</a><ul>
<li><a href="#tty_event_resize">Event: &#39;resize&#39;</a></li>
<li><a href="#tty_ws_columns">ws.columns</a></li>
<li><a href="#tty_ws_rows">ws.rows</a></li>
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<li><a href="#tty_tty_isatty_fd">tty.isatty(fd)</a></li>
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        <h1>TTY<span><a class="mark" href="#tty_tty" id="tty_tty">#</a></span></h1>
<pre class="api_stability api_stability_2">Stability: 2 - Stable</pre><p>The <code>tty</code> module houses the <code>tty.ReadStream</code> and <code>tty.WriteStream</code> classes. In
most cases, you will not need to use this module directly.</p>
<p>When Node.js detects that it is being run inside a TTY context, then <code>process.stdin</code>
will be a <code>tty.ReadStream</code> instance and <code>process.stdout</code> will be
a <code>tty.WriteStream</code> instance. The preferred way to check if Node.js is being run
in a TTY context is to check <code>process.stdout.isTTY</code>:</p>
<pre><code>$ node -p -e &quot;Boolean(process.stdout.isTTY)&quot;
true
$ node -p -e &quot;Boolean(process.stdout.isTTY)&quot; | cat
false
</code></pre><h2>Class: ReadStream<span><a class="mark" href="#tty_class_readstream" id="tty_class_readstream">#</a></span></h2>
<p>A <code>net.Socket</code> subclass that represents the readable portion of a tty. In normal
circumstances, <code>process.stdin</code> will be the only <code>tty.ReadStream</code> instance in any
Node.js program (only when <code>isatty(0)</code> is true).</p>
<h3>rs.isRaw<span><a class="mark" href="#tty_rs_israw" id="tty_rs_israw">#</a></span></h3>
<p>A <code>Boolean</code> that is initialized to <code>false</code>. It represents the current &quot;raw&quot; state
of the <code>tty.ReadStream</code> instance.</p>
<h3>rs.setRawMode(mode)<span><a class="mark" href="#tty_rs_setrawmode_mode" id="tty_rs_setrawmode_mode">#</a></span></h3>
<p><code>mode</code> should be <code>true</code> or <code>false</code>. This sets the properties of the
<code>tty.ReadStream</code> to act either as a raw device or default. <code>isRaw</code> will be set
to the resulting mode.</p>
<h2>Class: WriteStream<span><a class="mark" href="#tty_class_writestream" id="tty_class_writestream">#</a></span></h2>
<p>A <code>net.Socket</code> subclass that represents the writable portion of a tty. In normal
circumstances, <code>process.stdout</code> will be the only <code>tty.WriteStream</code> instance
ever created (and only when <code>isatty(1)</code> is true).</p>
<h3>Event: &#39;resize&#39;<span><a class="mark" href="#tty_event_resize" id="tty_event_resize">#</a></span></h3>
<p><code>function () {}</code></p>
<p>Emitted by <code>refreshSize()</code> when either of the <code>columns</code> or <code>rows</code> properties
has changed.</p>
<pre><code class="lang-js">process.stdout.on(&#39;resize&#39;, () =&gt; {
  console.log(&#39;screen size has changed!&#39;);
  console.log(`${process.stdout.columns}x${process.stdout.rows}`);
});
</code></pre>
<h3>ws.columns<span><a class="mark" href="#tty_ws_columns" id="tty_ws_columns">#</a></span></h3>
<p>A <code>Number</code> that gives the number of columns the TTY currently has. This property
gets updated on <code>&#39;resize&#39;</code> events.</p>
<h3>ws.rows<span><a class="mark" href="#tty_ws_rows" id="tty_ws_rows">#</a></span></h3>
<p>A <code>Number</code> that gives the number of rows the TTY currently has. This property
gets updated on <code>&#39;resize&#39;</code> events.</p>
<h2>tty.isatty(fd)<span><a class="mark" href="#tty_tty_isatty_fd" id="tty_tty_isatty_fd">#</a></span></h2>
<p>Returns <code>true</code> or <code>false</code> depending on if the <code>fd</code> is associated with a
terminal.</p>

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